Doctor' s Best SAM-e is proven to enhance mood and promote cognitive health. It is essential for the healthy metabolism of the major brain transmitters' dopamine, serotonin and norepinephrine. In addition, SAM-e promotes joint comfort and mobility and supports liver health and detoxification. SAM-e effectiveness has been published in 18 controlled human trials published over 40 years. Doctor' s Best SAM-e uses pharmaceutical grade materials. SAM-e is derived from the amino acid methionine and is one of the most important methyl donors in the central nervous system. SAM-e optimized for potency, stability, and to survive the stomach acid and reach the intestine (where it is absorbed). Effectiveness of SAM-e has been backed by at least 18 controlled human trials published over almost four decades.